CHARNLEY LOW-FRICTION ARTHROPLASTY OF THE HIP - 20-YEAR RESULTS WITH CEMENT

The first 333 Charnley (Thackray, United Kingdom) total hip arthroplas ties performed at the Mayo Clinic between 1969 and 1970 have been foll owed since that time. One hundred twelve patients (112 hips) remain al ive at 20 years. Clinical results remain excellent. The Mayo clinical and roentgenographic hip scoring system rates the results as good to e xcellent in 39 of 69 hips (with all necessary data to calculate the en tire score), fair in 13 hips, and poor in 17 hips. The clinical score alone showed satisfactory results in 77 of 112 hips. Some clinical det erioration was attributed to the advancing age of the patients (mean a ge at final follow-up evaluation, 84 years). Probable roentgenographic loosening (component migration, complete bone-cement, interface, radi olucent line greater than 1 mm, cement fracture) was noted in 12 of 69 acetabular components (17%) and 28 of 69 femoral components (36%). Tw o patients had required revision since the last report at 15 years for a total of 38 patients (32 revised, 4 Girdlestone arthroplasties, 2 s tem fractures not yet revised). The probability of surviving 20 years without revision of the components was 84% (83% for men, 85% for women ). The rates of loosening, revision; and failure (revision, Girdleston e, or symptomatic loosening) remain linear over 20 years of follow-up evaluation. If the probability of revision is based on patient age at the time of the initial total hip arthroplasty, there is a significant ly increased probability of revision in those patients less than 59 ye ars of age (27%) compared to those 59-65 years of age (13%), 65-70 yea rs (7.5%), and over 70 years (12%).